<?php
/*
 * Copyright 2023 Google LLC
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

namespace Google\ApiCore\Options;

use BadMethodCallException;
use Google\ApiCore\ValidationException;

/**
 * Trait implemented by any class representing an associative array of PHP options.
 * This provides validation and typehinting to loosely typed associative arrays.
 */
trait OptionsTrait
{
    /**
     * @param string $filePath
     * @throws ValidationException
     */
    private static function validateFileExists(string $filePath)
    {
        if (!file_exists($filePath)) {
            throw new ValidationException("Could not find specified file: $filePath");
        }
    }

    public function offsetExists($offset): bool
    {
        return isset($this->$offset);
    }

    #[\ReturnTypeWillChange]
    public function offsetGet($offset)
    {
        return $this->$offset;
    }

    /**
     * @throws BadMethodCallException
     */
    public function offsetSet($offset, $value): void
    {
        throw new BadMethodCallException('Cannot set options through array access. Use the setters instead');
    }

    /**
     * @throws BadMethodCallException
     */
    public function offsetUnset($offset): void
    {
        throw new BadMethodCallException('Cannot unset options through array access. Use the setters instead');
    }

    public function toArray(): array
    {
        $arr = [];
        foreach (get_object_vars($this) as $key => $value) {
            $arr[$key] = $value instanceof OptionsInterface
                 ? $value->toArray()
                 : $value;
        }
        return $arr;
    }
}
